Lincoln Electric 250 GXT manual Welding Process, Stick Constant Current Welding, ARC Gouging

b-4 OPERATION b-4

WELDING PROCESS

For any electrodes the procedures should be kept within the rating of the machine. For electrode infor- mation see the appropriate Lincoln publication.

STICK (CONSTANT CURRENT) WELDING

Connect welding cables to the "TO WORK” and "ELECTRODE” studs. Start the engine. Set the "Polarity” switch to the desired polarity. The “RANGE” switch markings indicate the maximum current for that range as well as the typical electrode size for that range. The “OUTPUT” Control provides fine adjust- ment of the welding current within the select range. For maximum output within a selected range set the “OUTPUT” Control at 10. For minimum output within a selected range set the “OUTPUT” Control at 5. (“OUT- PUT” Control settings below 5 may reduce arc stabili- ty) For best overall welding performance set the “RANGE” Switch to the lowest setting and the OUT- PUT” Control near the maximum to achieve the desired welding current.

RANGE SETTING	TYPICAL	CURRENT RANGE
	ELECTRODE SIzE
80 MAX.	3/32	50 TO 80 AMPS
130 MAX.	1/8	70 TO 130 AMPS
180 MAX.	5/32	110 TO 180 AMPS
250 MAX.	3/16	160 TO 250 AMPS

The Ranger® 250 GXT can be used with a broad range of AC and DC stick electrodes. See “Welding Tips 1” included with the Ranger® 250 GXT for elec- trodes within the rating of this unit and recommended welding currents of each.

TIG (CONSTANT CURRENT) WELDING

The Ranger® 250 GXT can be used in a wide variety of AC and DC Tungsten Inert Gas (TIG) welding applications for AC TIG Welding up to 200 amps and DC TIG welding up to 250 amps.

The K930 [ ] TIG Module installed on a Ranger® 250 GXT pro- vides high frequency and shielding gas control for AC and DC GTAW (TIG) welding processes. The TIG Module allows full range output control.

When using the Ranger® 250 GXT for AC TIG welding of alu-

minum the following settings and electrodes are recommended: For AC TIG Welding, the maximum TIG Welding out-

SETTINGS FOR PURE TUNGSTEN

TUNGSTEN	RANGE SWITCH	APPROXIMATE
DIAMETER (in.)	SETTINGS	CURRENT RANGE
1/8	80 or 130	100 - 300 Amps
3/32	80	45	-	140	Amps
1/16	80	45	-	100	Amps

SETTINGS FOR  1% THORIATED TUNGSTEN

TUNGSTEN	RANGE SWITCH	APPROXIMATE
DIAMETER (in.)	SETTINGS	CURRENT RANGE
1/8	80, 130, or 180	80	-	225	Amps
3/32	80 or 130	50	-	180	Amps
1/16	80	45 - 120 Amps

put currents on each range setting will be approxi- mately 50% higher than those marked on the name- plate. This is due to the special nature of the AC TIG welding arc. Do not AC TIG weld on the 250 Amp set- ting. The output may exceed the rating of the Ranger® 250 GXT.

WIRE FEED WELDING PROCESSES (CONSTANT VOLTAGE)

The Innershield® electrode recommended for use with the Ranger® 250 GXT is NR®-211-MP. The electrode sizes and welding ranges that can be used with the Ranger® 250 GXT are shown in the following table:

The Ranger® 250 GXT is recommended for limited

Diameter	Wire Speed			Approximate
(in.)	Range In./Min.			Current Range
.035	80	- 110		75A to 120A
.045	70	- 130		120A to 170A
.068	40	-	90	125A to 210A
5/64	50	-	75	180A to 235A

“MIG” welding (GMAW - gas metal arc welding). The recommended electrodes are .030” and .035” L-50 and L-56. They must be used with a blended shield- ing gas such as C25 (75% Argon - 25% CO2). The welding ranges that can be used with the Ranger®

250 GXT are shown in the following table:

Diameter	Wire Speed		Approximate
(in.)	Range In./Min.		Current Range
.030	75	- 300	50A to 130A
.035	100	- 250	80A to 175A
.045	125	- 200	145A to 200A

ARC GOUGING

The Ranger® 250 GXT can be used for limited arc gouging.

Set the Range switch to adjust output current to the desired level for the gouging electrode being used according to the ratings in the following table:

ELECTRODE SETTING	CURRENT RANGE (DC, electrode positive)
1/8	30	-	60 Amps
5/32	90	-	150 Amps
3/16	150 - 250 Amps

RANGER® 250 GXT